WP_Comment_Query with WP_Meta_Query integration

Description

Basically the title says it all. What I'd like to see in WordPress is an implementation of the WP_Meta_Query that was intorduced in 3.2 for the comments query as well as ordering by meta values.

Basically if those features are implemented, developers will have greater flexibility about comments - the first things that come to mind are rating system(I know there should be a plugin out there for that already), separating comments by some parameter(let's say age/sex/country/etc, if there is some kind of sociological study) and many more.

I stumbled upon this quite recently when I was making an extension for qTranslata and I had to get comments by specific meta value - I had to either write custom MySQL(at which I'm not really good), or implement the meta query.

I'm attaching the diff file that I made(I've tested that with 3.4) for wp-includes/comments.php